Sixteen-year-old Murad Rahimov peered down into a gigantic space he had only dreamed about before: the world's largest clean room, kept scrupulously free of any dust or contamination, where NASA assembles and tests spacecraft before launch.

Murad's eyes gleamed and a smile played on his face as he took it all in — the scientists encased in sterile white suits; the replica of the massive new space telescope, the most powerful ever built, that will study the first galaxies born after the Big Bang.

Murad is obsessed with space. He has been ever since he was three, back in his home country Uzbekistan. His young imagination was sparked when his aunt gave him a picture book about space, and he couldn't stop looking at the images of the solar system. Soon after, he told his parents his dream: He wanted to become an astronaut and work for NASA.

On this recent day, he was getting a private tour of NASA's Goddard Space Flight Center in Greenbelt, Md., thanks to an NPR listener who heard about Murad's passion for space in a story that aired earlier this year. In January, NPR profiled the Rahimov family on the day they became naturalized as U.S. citizens. The Rahimovs immigrated to the U.S. from Uzbekistan in 2010, when Murad was nine. When they first landed in Kansas City, Murad spoke no English. Now, heading into his junior year of high school, he's on an accelerated track, taking extra classes in the summer and packing his schedule with AP courses.

Listener Aaron Schnittman heard that story on the radio, and his ears perked up when he heard that Murad's goal is to work for NASA. He emailed NPR that same day, that his brother is a research astronomer working for NASA at Goddard. "I think it would be a cool follow up to connect the son to my brother and help him make the connections needed to pursue studies in astronomy," he wrote.

Cool, indeed. The connection was made, emails were exchanged, and last week, at the invitation of Jeremy Schnittman, Murad and his mother, Limara Rahimova, made the trip to Goddard outside Washington, D.C. Schnittman, an astrophysicist who specializes in black holes, spent several hours showing the Rahimovs the inner workings of the space flight center and sharing his enthusiasm for space science.

Murad was clearly in his element, sporting a t-shirt with a picture of the Millennium Falcon spaceship from Star Wars, and a line from the movie: "the fastest hunk of junk in the galaxy."

He and his mother got to see the giant cryo-vac chamber where spacecraft are tested to find out if they'll withstand the extreme temperatures of space. They walked inside the acoustic chamber that blasts spacecraft with earsplitting sound to simulate the vibration of launch. They toured the laser lab where scientists are fine-tuning measurements to detect gravitational waves. "Amazing," Murad marveled.

Back in his office, ("black hole central," as he calls it) Schnittman talked with Murad about his research into how light gets bent around black holes. Naturally, they both share a hero in Albert Einstein, whose photo Schnittman keeps pinned above his desk. "It's remarkable," Schnittman said. "It's over 100 years since Einstein did all of this stuff, and still, everything is Einstein. Einstein, Einstein, Einstein."

When Murad mused about the possibilities of time travel, Schnittman sounded optimistic. "It's really not that much of a stretch to say that we're one step closer to time travel," he told Murad. "This is something that Einstein predicted 100 years ago. According to the theory, the equations, time travel should be possible. The trick is just building it and getting it to work, but as far as we can tell, there's no rule against it."

The astrophysicist and the would-be astronaut parted ways with the promise to stay in touch.

Later Murad said he loves science because it shows "the sheer awesomeness, the sheer scale of how insignificant and alone we are in the universe. All these petty fights that people have between themselves, they are just insignificant. When you start thinking about space, you get lost in the vastness of it. That's what captivates me the most."

Now that he's a U.S. citizen, he believes his dream of becoming an astronaut is more within reach. He and his brother automatically became citizens when their parents did. Murad was at school the day they took the oath: "I came home and looked at my parents, and felt all this pride," he said. "You could sense that something has changed. They were smiling from ear to ear."

For his mother, Limara, becoming a U.S. citizen has grounded her in a new way. "I felt before like I'm between countries," she said. "But now I feel like I'm staying ...both my feet here in this land."

Limara works at a school, and each morning they all stand for the pledge of allegiance. Before, she said, "it didn't touch me. But now, yes! And I know what each word in the pledge of allegiance means. And it means, for me, a lot."

As for Murad? The rising high school junior has his sights set on going to Cal Tech, and on the Mars mission he dreams of one day leading. "Some people, they tell me to try to get a real job," he said, "of maybe not shooting so high. But nah. I'm shooting for it. I'm gonna chase my dreams."

Meantime, there's a celestial show about to happen, one he's been excited about for years: the total solar eclipse.

Murad's hometown, Kansas City, is a perfect spot to see it: right in the path of totality.

Next Monday he will be outside, watching in awe as the moon slides over the sun, and dreaming big dreams of space.

Copyright 2017 NPR. To see more, visit http://www.npr.org/.

RACHEL MARTIN, HOST:

Back in January, we introduced you to the Rahimov family. They had immigrated from Uzbekistan, and we met them on the day they became U.S. citizens in Kansas City, Mo. In that story, we heard 16-year-old Murad Rahimov talk about how much he loves astronomy and his dream to work for NASA.

As it happens, a NASA astrophysicist was listening to that story too. And he reached out. Last week, the two met up at the Goddard Space Flight Center outside Washington, D.C. NPR's Melissa Block picks up their story.

MELISSA BLOCK, BYLINE: The astrophysicist and the young would-be astronaut first connected by email.

MURAD: (Reading) Hello, Dr. Schnittman, how are you? Thanks so much for having the interest in me.

BLOCK: Murad wrote that he's been fascinated by space since he was 3, that his dream is to lead a mission to Mars.

MURAD: (Reading) I find it unusually strange how most people don't have the curiosity and drive to understand things larger than themselves.

BLOCK: The NASA scientist, Dr. Jeremy Schnittman who specializes in black holes, invited Murad to come for a tour of Goddard. And last week...

JEREMY SCHNITTMAN: Hi, welcome.

BLOCK: ...Murad and his mother Limara took him up on the offer.

SCHNITTMAN: You have a good trip?

MURAD: It was great.

BLOCK: Murad is wearing a T-shirt with a picture of the Millennium Falcon spaceship from "Star Wars" and this line from the movie - the fastest hunk of junk in the galaxy. And as he tours the Goddard Space Flight Center, you can tell he's in his element.

BLOCK: Murad gets to see a giant cryo-vac chamber and a new instrument measuring the densest known objects in the universe.

SCHNITTMAN: ...Catching X-rays from things like neutron stars and black holes and counting them up.

MURAD: This is really an amazing tour.

SCHNITTMAN: Well, good, I'm glad you were able to do it.

BLOCK: Later, Murad tells me that his dream of becoming an astronaut feels more within reach now that he's a U.S. citizen. He and his brother automatically became citizens when their parents did. Murad was at school the day they took that oath.

MURAD: I came home, and I looked at my parents and felt all this pride. You could sense that something has changed. They were smiling from ear to ears.

BLOCK: Limara works at a school. And every morning, they all stand for the Pledge of Allegiance. Before, she says, it didn't touch her.

LIMARA RAHIMOVA: But now, yes, and I know what each word in the Pledge of Allegiance means. And it means, for me, a lot.

BLOCK: As for Murad, the rising high school junior has his sights set on going to Caltech and on that Mars mission he wants to lead.

MURAD: Some people, they tell me to try to get, like, a real job - of maybe not shooting so high. But nah (ph), I'm shooting for it. I'm going to chase my dreams.

BLOCK: Meantime, there's a celestial show about to happen, one he's been excited about for years - the total solar eclipse. Murad's hometown, Kansas City, is a perfect spot to see it right in the path of totality. Next Monday, he'll be outside watching as the moon slides over the sun - watching in awe and dreaming big dreams of space. Melissa Block, NPR News.